Distorted Android

Enrich the Multiblur app.

It now automatically chooses OpenGL ES 2.0 and GLSL 100 or OpenGL ES 3.0 and GLSL 300.

Postprocessing effects will not work on OpenGL ES 2.0 contexts.

as clearing Depth has been fixed in 580f7d10, we can now use this API in the 'FBO' app.

New 'glClearColor' and 'glClearDepthf' APIs in OutputSurface. This fixes the 'transparency' regressions from last commit.

Now there's a single place one can have a look at all the Meshes being rendered to a OutputSurface: OutputSurface.renderChildren().
This will need to get modified for per-object post-processing.

Minor

1. Move to Gradle 25.0.0
2. Bugfix in DistortedNode

Speed up shaders (both compilation and execution) by explicitly enabling only the needed effects.

Fix Crawl transparency in StarWars.

Small improvements for StarWars, but the main issue - non-working transparency of the Crawl - not solved.

Fixes for z-fighting.

Make it possible to render each DistortedNode with adjustable OpeGL state (writeing to Color, Depth,Stencil buffers, DEPTH, STENCIL, BLENDING on.off, etc)

The only operation which is now enabled 'statically' in render() is blending.

1) stop culling back face
2) reset OpenGL state beore each render (and not in onCreate)
3) Improve Matrix3D so that we can test negative Scales

A Lot of fixes for the issues uncovered by Olimpic.

Still at least 1 known issue: sometimes, when we re-add a Surface, some garbage pops up on the screen for a brief split second. Visible in Olimpic.

a few lame fixes for the issues uncovered by Olimpic but it is still wrong

Further improve Olimpic. This seems to expose some Node bugs.

Improve Olimpic.

Improve Olimpic.

- workaround for the issue with flashing in StarWars
- return number of objects rendered from OutputSurface.render() and use this in Olympic
- rework tree isomorphism so that it now works even if we don't render the whole tree (and also we don't have to reset() the Tree anymore!)...

Fix issue with Blur / Multiblur apps

1. Make it possible to enable/disable DEPTH test when rendering to a Screen
2. Using this, remove the 'Root' Node from StarWars.

A lot of different fixes.

A lot of issues still there:

1) if we only render part of the tree, tree isomorphism will sometimes not work correctly
2) when we change Effects that are inside Trees mid-render, even if we detach() the affected parts of the Tree first, for the last frame the new Effects will be used...

New, cleaner way to create/destroy DistortedSurfaces.

Serious regression in StarWars (crashes!). Looks like the Node's internal FBO is being deleted and not re-created in time.

Minor.